1,219 research outputs found
Memantinium chloride 0.1-hydrate
The crystal structure of the title compound, C12H22N+·Cl−·0.1H2O, consists of (3,5-dimethyl-1-adamantyl)ammonium chloride (memantinium chloride) and uncoordinated water molecules. The four six-membered rings of the memantinium cation assume typical chair conformations. The Cl− counter-anion links with the memantinium cation via N—H⋯Cl hydrogen bonding, forming channels where the disordered crystal water molecules are located. The O atom of the water molecule is located on a threefold rotation axis, its two H atoms symmetrically distributed over six sites; the water molecule links with the Cl− anions via O—H⋯Cl hydrogen bonding
Quantum state transfer through a spin chain in a multi-excitation subspace
We investigate the quality of quantum state transfer through a uniformly
coupled antiferromagnetic spin chain in a multi-excitation subspace. The
fidelity of state transfer using multi-excitation channels is found to compare
well with communication protocols based on the ground state of a spin chain
with ferromagnetic interactions. Our numerical results support the conjecture
that the fidelity of state transfer through a multi-excitation subspace only
depends on the number of initial excitations present in the chain and is
independent of the excitation ordering. Based on these results, we describe a
communication scheme which requires little effort for preparation.Comment: 5 pages, 4 figure
Triamcinolone acetonide acetate
In the crystal structure of the title compound [systematic name: 2-(4b-fluoro-5-hydroxy-4a,6a,8,8-tetramethyl-2-oxo-2,4a,4b,5,6,6a,9a,10,10a,10b,11,12-dodecahydro-7,9-dioxapentaleno[2,1-a]phenanthren-6b-yl)-2-oxoethyl acetate], C26H33FO7, the molecules are connected by intermolecular O—H⋯O hydrogen bonds into an infinite supramolecular chain along the b axis. The molecular framework consists of five condensed rings, including three six-membered rings and two five-membered rings. The cyclohexa-2,5-dienone ring is nearly planar [maximum deviation = 0.013 (3) Å], while the cyclohexane rings adopt chair conformations. The two five-membered rings, viz. cyclopentane and 1,3-dioxolane, display envelope conformations
Bupropion hydrobromide propanol hemisolvate
The title compound {systematic name: N-[1-(3-chlorophenyl)-1-oxopropan-2-yl]-tert-butanaminium bromide propanol hemisolvate}, C13H19ClNO+·Br−·0.5C3H8O, crystallizes with two independent bupropion hydrobromide ion pairs and a solvent 1-propanol molecule in the asymmetric unit. In both molecules, the expected proton transfer from HBr to the amino group of the bupropion molecule is observed, and intra- and intermolecular N—H⋯Br hydrogen-bond interactions are formed. These interactions link the molecules into hydrogen-bond dimers. The side chains of the two cations have slightly different orientations. The 1-propanol solvent molecule is linked to a bromide ion by an O—H⋯Br hydrogen bond
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